An autopsy case of protracted necrotic encephalitis with marked atrophy of unilateral temporal lobe.

Clinical and neuropathological findings in a case of an unusually protracted encephalitis have been described. The patient was a 44-year-old man who experienced mental deterioration, right abducens and facial paresis, right and, subsequently, left hemiparesis, and consciousness disturbance with an intermittent low grade fever and occasional headache during one year and three months. Electroenphalograms showed periodic lateralized epileptiform discharges. Virus titers including herpes simplex virus were all normal. Neuropathological examinations revealed marked atrophic changes in the right temporal lobe, insular lobe and hippocampus with minimal inflammatory signs. The distribution of the lesions was almost identical with that of acute necrotic encephalitis or herpes simplex encephalitis despite its unusually protracted course.